What use is an 829B tube?
 

Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.

I put a pair on my office credenza just to look geeky cool. Fresh
out of the box as NOS they look amazing - just like they were made
yesterday. It's a pity they have no value - maybe as a homebrew
project??

So can someone tell me what they would have been used for?
Something tells me they're a VHF power tube.

Any application as a one-tube QRP rig of any sort? Any stories
about using them in the past? I've built a lot of little rigs over the
years, but never knew about the 829

Thanks,

Dave

"Dave" wrote in message
news.com...
Hi all,

I just found several 829B tubes - believe it or
not in my garage - I
must have got them in a box of stuff at a ham
fest at one time.
A check on Ebay shows they're pretty much
worthless for the sake
of dollars, but they're so COOL! With the two
plate caps that are
actually just stiff pins, they look like little
Martians.

I put a pair on my office credenza just to look
geeky cool. Fresh
out of the box as NOS they look amazing - just
like they were made
yesterday. It's a pity they have no value -
maybe as a homebrew
project??

So can someone tell me what they would have been
used for?
Something tells me they're a VHF power tube.

Any application as a one-tube QRP rig of any
sort? Any stories
about using them in the past? I've built a lot
of little rigs over the
years, but never knew about the 829

Thanks,

Dave

The last rig I saw using an 829 was about 35 to 50
watts in the 50 to 70 MHZ range.
Makes a good 2 Meter amp.
Nice tube. Not QRP IMO...
I have three of them around here somewhere.

"Dave" wrote in message
news.com...
Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.


They are WWII military tubes. As you surmised, mostly for VHF
work. The smaller cousin was the 832B tube, used in the
SCR-522 transmitter (driver, PA stages). A very popular conversion
for 2-meter AM through the 50s and early 60s. The modern
version of the 829 is the 5894 power tube.


Pete

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.

I put a pair on my office credenza just to look geeky cool. Fresh
out of the box as NOS they look amazing - just like they were made
yesterday. It's a pity they have no value - maybe as a homebrew
project??

So can someone tell me what they would have been used for?
Something tells me they're a VHF power tube.

They are about the same as a pair of 6146 tubes in one envelope but are more
efficient at higher frequencies.
Good for about 100 watts out at 2 meters and somewhat ueuable at 440 mhz.
I think the old VHV book had an amp in it for 144 mhz that was rated for
about 40 watts out on AM and more on CW/SSB.

They also make good push-pull stereo amps :-)

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca

Motorola used them in the "K" strip series of transmitters....60 watts at
150Mhz. Usually driven with a 2E26. That tube with 700 Volts on the plates
would make that kind of power all day...Eddie

"Dave" wrote in message
news.com...
Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.

I put a pair on my office credenza just to look geeky cool. Fresh
out of the box as NOS they look amazing - just like they were made
yesterday. It's a pity they have no value - maybe as a homebrew
project??

So can someone tell me what they would have been used for?
Something tells me they're a VHF power tube.

Any application as a one-tube QRP rig of any sort? Any stories
about using them in the past? I've built a lot of little rigs over the
years, but never knew about the 829

Thanks,

Dave

Dave wrote:

I just found several 829B tubes - believe it or not in my garage...

So can someone tell me what they would have been used for?
Something tells me they're a VHF power tube.

You've gotten some good responses from some others in the NG.
The most unusual application for the 829B that I saw was their
being used to drive the magnetic-core memory modules in the
Whirlwind I computer racks on display in the Computer Museum
in Boston. The sockets may have originally been designed for
832's and "upgraded" to 829's for more drive or longer life.

Jim Bromley, K7JEB
Glendale, AZ

they are 2 ea 6l6 tubes in 1 envelope and were used for a lot of vhf
transmitters you get 40 to 60 watts in a class c fm transmitter.
"Dave" wrote in message
news.com...
Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.

I put a pair on my office credenza just to look geeky cool. Fresh
out of the box as NOS they look amazing - just like they were made
yesterday. It's a pity they have no value - maybe as a homebrew
project??

So can someone tell me what they would have been used for?
Something tells me they're a VHF power tube.

Any application as a one-tube QRP rig of any sort? Any stories
about using them in the past? I've built a lot of little rigs over the
years, but never knew about the 829

Thanks,

Dave

On Fri, 06 Feb 2004 01:03:55 GMT, "Dave" wrote:

|Hi all,
|
|I just found several 829B tubes - believe it or not in my garage - I
|must have got them in a box of stuff at a ham fest at one time.
|A check on Ebay shows they're pretty much worthless for the sake
|of dollars, but they're so COOL! With the two plate caps that are
|actually just stiff pins, they look like little Martians.
|
|I put a pair on my office credenza just to look geeky cool. Fresh
|out of the box as NOS they look amazing - just like they were made
|yesterday. It's a pity they have no value - maybe as a homebrew
|project??
|
|So can someone tell me what they would have been used for?
|Something tells me they're a VHF power tube.
|
|Any application as a one-tube QRP rig of any sort? Any stories
|about using them in the past? I've built a lot of little rigs over the
|years, but never knew about the 829

I used one on two meters in the early 60's. The amp was of course
push-pull and had a tuned line plate circuit with link coupling. I
ran AM and CW and used the modulated high voltage out of my Heathkit
DX-100 for plate and screen voltage.

The original exciter was a converted SCR-522, which used the 829's
baby brother, the 832 as frequency multipliers and final. Later I
replaced the 829 with a 5894 and the 832s with a baby version of the
'94, whose part number escapes me at the moment (6907 I think).

These later tubes were more efficient at vhf and were tetrodes rather
than the 832-829 "beam-power" tubes. The 832 was sort of like a pair
of 2E26s sharing a cathode and the 829 was sort of like a pair of
807s.

Eventually, I replaced the clunky '522 with a more compact exciter out
of the Handbook that used somethin' or the other as
oscillator/doubler/tripler and a 6360 tripler driving another 6360.

Real progress came when I converted the second 6360 to a high level
mixer driven with a Central Electronics 10A SSB exciter. (I don't even
want to think what the IMD out of this mess must have been.)

Many thanks to all who replied, both here and by email.
They sound like a great tube for LOTS of purposes. My
favorite suggestion was building a regen, using each
half in place of the 6AQ5's called for in the ARRL handbook
design from the 50's!

How about an oscillator / amplifier for HF, running low
plate voltage for a relatively low RF output? Seems they
should be able to do that - and having a separate oscillator
stage it wouldn't be prone to runaway and exessive crystal
current. And it would look VERY cool!

What sort of plate caps were used? There are just pins, and
it looks almost as if there would have been a ceramic gizmo
like a tube socket to have bridged the two of them....

Again, thanks for the info!!

Dave